Change information: information about the change
that triggered this event; usually service provider-specific or server-specific
information.

Note that the event source is always the same EventContextinstance that the listener has registered with.
Furthermore, the names of the bindings in
the NamingEvent are always relative to that instance.
For example, suppose a listener makes the following registration:

OBJECT_REMOVED

OBJECT_RENAMED

public static final int OBJECT_RENAMED

Naming event type for indicating that an object has been renamed.
Note that some services might fire multiple events for a single
logical rename operation. For example, the rename operation might
be implemented by adding a binding with the new name and removing
the old binding.

The old/new binding in NamingEvent may be null if the old
name or new name is outside of the scope for which the listener
has registered.

When an interior node in the namespace tree has been renamed, the
topmost node which is part of the listener's scope should used to generate
a rename event. The extent to which this can be supported is
provider-specific. For example, a service might generate rename
notifications for all descendants of the changed interior node and the
corresponding provider might not be able to prevent those
notifications from being propagated to the listeners.

OBJECT_CHANGED

public static final int OBJECT_CHANGED

Naming event type for indicating that an object has been changed.
The changes might include the object's attributes, or the object itself.
Note that some services might fire multiple events for a single
modification. For example, the modification might
be implemented by first removing the old binding and adding
a new binding containing the same name but a different object.

NamingEvent

The names in newBd and oldBd are to be resolved relative
to the event source source.
For an OBJECT_ADDED event type, newBd must not be null.
For an OBJECT_REMOVED event type, oldBd must not be null.
For an OBJECT_CHANGED event type, newBd and
oldBd must not be null. For an OBJECT_RENAMED event type,
one of newBd or oldBd may be null if the new or old
binding is outside of the scope for which the listener has registered.

Parameters:

source - The non-null context that fired this event.

type - The type of the event.

newBd - A possibly null binding before the change. See method description.

oldBd - A possibly null binding after the change. See method description.

getEventContext

Retrieves the event source that fired this event.
This returns the same object as EventObject.getSource().

If the result of this method is used to access the
event source, for example, to look up the object or get its attributes,
then it needs to be locked because implementations of Context
are not guaranteed to be thread-safe
(and EventContext is a subinterface of Context).
See the
package description
for more information on threading issues.

Returns:

The non-null context that fired this event.

getOldBinding

The binding must be nonnull if the object existed before the change
relative to the source context (getEventContext()).
That is, it must be nonnull for OBJECT_REMOVED and
OBJECT_CHANGED.
For OBJECT_RENAMED, it is null if the object before the rename
is outside of the scope for which the listener has registered interest;
it is nonnull if the object is inside the scope before the rename.

The name in the binding is to be resolved relative
to the event source getEventContext().
The object returned by Binding.getObject() may be null if
such information is unavailable.

Returns:

The possibly null binding of the object before the change.

getNewBinding

The binding must be nonnull if the object existed after the change
relative to the source context (getEventContext()).
That is, it must be nonnull for OBJECT_ADDED and
OBJECT_CHANGED. For OBJECT_RENAMED,
it is null if the object after the rename is outside the scope for
which the listener registered interest; it is nonnull if the object
is inside the scope after the rename.

The name in the binding is to be resolved relative
to the event source getEventContext().
The object returned by Binding.getObject() may be null if
such information is unavailable.